Morphology of otoliths in some fishes of Caspian Sea basin

Otoliths or ear stones are hard skeletal elements having mineral and organic substances in the head of fishes. There are three pairs of otoliths which are called sagitta, lapillus and asteriscus. In the present research work, otoliths of 13 fish species from 12 genera, 4 families and 4 orders (Cypriniformes, Perciformes, Esociformes and Mugilliformes) were studied. Results showed that shape, size and structure of otoliths in studied fishes are diverse and species specific. It was revealed that asteriscus otolith in Cyprinidae and sagitta in Gobiidae, Mugillidae and Esocidae are the biggest otoliths. There were variations in shapes of astersiscus (round, oval and square) in all four families. These variations could be used in taxonomic studies, paleontology and study of food and feeding habits of aquatic vertebrates such as mammals, birds and fishes.